Niacinamide para UV Protection (Internal Photoprotection)
A Evidências Vários grandes ensaios clínicos mostram de forma consistente benefícios significativos.The ONTRAC trial (NEJM 2015) found oral nicotinamide 500 mg twice daily reduced new nonmelanoma skin cancers by 23% and actinic keratoses by 11% in high-risk individuals, supporting cellular DNA repair via NAD+ replenishment.
Conclusão
The ONTRAC trial (NEJM 2015) found oral nicotinamide 500 mg twice daily reduced new nonmelanoma skin cancers by 23% and actinic keratoses by 11% in high-risk individuals, supporting cellular DNA repair via NAD+ replenishment.
Key Study Findings
População: Overview of reviews on niacin/nicotinamide adverse effects
População: High-risk NMSC patients (RCTs)
População: None
Key Statistics
5
Estudos
686
Participantes
Positive
Nota
Referenced Papers
Dosage & Usage
mg = milligrams · mcg = micrograms (1,000× smaller) · IU = International Units
Dosagens Comumente Utilizadas
- general:
- 14-16 mg/day NE (RDA)
- skinhealth:
- 500-1,500 mg/day oral nicotinamide
Limite superior: 35 mg/day for niacin (flushing form); nicotinamide well-tolerated up to 3,000 mg/day
Dosagens Estudadas em Pesquisas
| Dosagem | Duração | Efeito | N |
|---|---|---|---|
| F1: biotin 0.5%, caffeine 2.0%, niacinamide 2.0%; F2: finasteride 0.1%, minoxidil 1.0%, tretinoin 0. | 26 weeks | Positive | -- |
| Vitamin B complex (various B vitamins including niacinamide/NAD+ precursor) | -- | Positive | -- |
| None | -- | Mixed | -- |
| Nicotinamide (vitamin B3) | -- | Positive | -- |
| None | -- | Mixed | -- |
| None | -- | Mixed | -- |
| Niacinamide up to 5%; Niacin up to 0.1% | -- | Mixed | -- |
Melhor horário: With meals; can be split into 2-3 doses
Safety & Side Effects
Efeitos Colaterais Relatados
- ⚠ Generally well-tolerated (no flushing unlike niacin)
- ⚠ Mild gastrointestinal discomfort at high doses
- ⚠ Rare hepatotoxicity at very high doses (> 3,000 mg/day)
Interações Conhecidas
- ● Anticonvulsants (carbamazepine — may increase niacinamide levels)
- ● Hepatotoxic drugs (potential additive liver effect at high doses)
- ● Isoniazid (competes for NAD+ pathways)
Ingestão máxima tolerável: 35 mg/day for niacin (flushing form); nicotinamide well-tolerated up to 3,000 mg/day
Consulte sempre o seu profissional de saúde antes de iniciar qualquer suplemento.Sempre consulte seu profissional de saúde antes de iniciar qualquer suplemento.
Frequently Asked Questions
Does Niacinamide help with UV Protection (Internal Photoprotection)?
How much Niacinamide should I take for UV Protection (Internal Photoprotection)?
Are there side effects of Niacinamide?
How strong is the evidence for Niacinamide and UV Protection (Internal Photoprotection)?
Related Evidence
Outros ingredientes para UV Protection (Internal Photoprotection)
Niacinamide para outras condições
References
- [1] Su Ling Young et al.. Eye (Lond). 2025. The adverse effects of oral niacin/nicotinamide - an overview of reviews. doi:10.1038/s41433-025-04027-2 PubMed
- [2] Carolina Schettino Kegele et al.. Int J Pharm Compd. 2025. Personalized Compounded Hair Loss Treatments: A Compatibility Assessment of the TrichoConcept™ Vehicle Line. PubMed
- [3] Feiya Du et al.. Int J Vitam Nutr Res. 2025. Advanced Applications of Vitamin B Complex in Plastic and Cosmetic Surgery: Mechanisms and Therapeutic Benefits. doi:10.31083/IJVNR39087 PubMed
- [4] Giulio Tosti et al.. Nutrients. 2023. The Role of Nicotinamide as Chemo-Preventive Agent in NMSCs: A Systematic Review and Meta-Analysis. doi:10.3390/nu16010100 PubMed
- [5] Katherine G Thompson et al.. J Am Acad Dermatol. 2021. Dietary supplements in dermatology: A review of the evidence for zinc, biotin, vitamin D, nicotinamide, and Polypodium. doi:10.1016/j.jaad.2020.04.123 PubMed
- [6] Reed Huber et al.. Skin Therapy Lett. 2020. Nicotinamide: An Update and Review of Safety & Differences from Niacin. PubMed
- [7] Cosmetic Ingredient Review Expert Panel. Int J Toxicol. 2005. Final report of the safety assessment of niacinamide and niacin. doi:10.1080/10915810500434183 PubMed
Aviso Legal da FDA: Estas declarações não foram avaliadas pela Food and Drug Administration. Os produtos e informações neste site não se destinam a diagnosticar, tratar, curar ou prevenir qualquer doença. As notas de evidência apresentadas são baseadas em nossa análise de pesquisas revisadas por pares publicadas e não constituem aconselhamento médico. Sempre consulte seu profissional de saúde antes de iniciar qualquer regime de suplementação.